Embodiments of the present invention relate to the field of image processing for 3D display of a patient's organ and, more particularly, to the field of image processing for 3D display of a patient's organ in which a surgical instrument is positioned.
Techniques exist which enable real-time visualization of a surgical instrument, in situ, during a surgical procedure, such as a needle, catheter, or straight or spiral wire guide.
Amongst these techniques, fluoroscopy imaging gives real-time knowledge of the position of the surgical instrument. Fluoroscopy imaging enables display of two-dimensional images (2D) of a region of interest in which a surgical instrument has been inserted. Fluoroscopy imaging comprises the use of an X-ray source and a fluorescent monitor between which the patient to be operated on is positioned. The practitioner is then able to track the position of the surgical instrument on the screen and to control the procedure. Modern fluoroscopy imaging, instead of the fluorescent monitor, uses a flat digital sensor and a CCD video camera enabling the recording of 2D images and their display on a screen.
Fluoroscopy imaging only enables the display of 2D images thereby compelling the practitioner to interpret and mentally reconstruct a 3D image in order to determine exactly where the surgical instrument is positioned.
Tomographic imaging enables the construction of images in three dimensions (3D) and provides images corresponding to cross-sectional slices of parts of the patient's body. Thus, the position of the instrument relative to the patient's body can be evaluated.
Although it has numerous advantages, tomographic imaging also has some disadvantages. First, in order to be able to reconstruct a 3D image of the patient' body, several 2D images at different angle positions of a C-arm carrying a radiation source must be acquired. The patient is therefore subjected to radiation doses. In addition, reconstruction of the 3D image is time-consuming. Finally, the display obtained using usual tomographic imaging methods is not optimized. A large volume of the patient's body is reconstructed whereas the practitioner only views those slices which contain the surgical instrument.